1. Field
The invention relates to communication between a transmitter and a receiver.
2. Description of the Related Art
An electronic communication system often has a module which limits the bandwidth of the system. For example, an FDD (Frequency Division Duplex) system, where a bandwidth covering a band between uplink and downlink transmissions may be tens or hundreds of megahertz, requires at least two radio channels in a radio channel emulator since the bandwidth of one channel in the radio channel emulator is not broad enough to include both uplink and downlink. Correspondingly, a TDD (Time Division Duplex) system also requires two radio channels in the radio channel emulator since the channel of uplink may be different from that of downlink.
Such an excessive use of radio channels of the radio channel emulator leads to waste of resources, a complicated system and potentially to a situation where the number of required radio channels is higher than the number of available radio channels in the radio channel emulator. A plurality of communication systems have similar problems due to the bandwidth as a bottleneck. Hence, there is a need for a better system.